Insulated masonry building block construction has varied widely in form. Loose insulation is sometimes introduced in situ after a wall has been constructed or partially constructed of masonry building blocks. Insulation has also been molded directly in the cavities of such blocks. Further, various special types of blocks have been provided with insulation mounted internally or secured externally.
Thereto, one form of block insulation, which has gained wide commercial acceptance, is disclosed in U.S. Pat. No. 3,885,363 to Richard W. Whittey entitled INSULATED BLOCK and in U.S. Pat. No. 4,027,445, to David L. Nickerson entitled INSULATED BLOCK. As disclosed therein, preformed insulating inserts are introduced to the cavities of conventional masonry building blocks at the block plant after the blocks have been formed and the blocks may thereafter be handled during transport and construction in the conventional manner of uninsulated blocks. Obvious and substantial advantages in efficiency, convenience and economy are thus achieved.
Even with the last above mentioned insulating technique however, the U-Values of the combined building block and insert may not be as low as desired for some installations. The core areas are effectively insulated by the insulating inserts but the mortar joints and the transverse webs, usually three in number and, extending between inner and outer side sections, result in substantial heat transfer conductively therethrough. To date there has been no effective solution to this problem. There are also of course other known problems with masonry building blocks such as the migration of moisture therethrough.
It is the general object of the present invention to provide an improved insulated masonry building block wherein a significant improvement in U-Values is achieved in the range 0.05 to 0.10 BTU/FT.sup.2 HRF.degree., wherein the insulation is applied at the block plant with substantial savings in cost, and wherein substantial improvement is achieved in reducing moisture migration or transmission through the blocks.